I am trying to brew GIN at home with wild Sloe berries.
How to dry sloe berries without losing it's useful fungal coating for sloe GIN?
One doesn't brew gin from sloe berries, you flavour gin with the sloes.
There is no need to dry the sloes. Just pop them in a bottle with the gin and some sugar and leave for a couple of months. There are plenty of recipes if you look for them, and not a little voodoo. Some people like to freeze the sloes first, others will prick them (with a thorn from the bush they were picked on) to let the juice out. You can experiment with the amount of sugar. Don't worry about the blush of yeast on the berries, this will get killed by the alcohol in the gin pretty rapidly.
There is no home brewing, fermentation or distillation involved, just the slow steeping of the fruit.